The connection of a towing vehicle to a trailer, such as those commonly used for carrying boats, campers and the like, conventionally requires that the towing vehicle be backed up toward the trailer until the trailer hitch components are in suitable relative position. For convenience a caster wheel is often connected to the trailer tongue in order to raise the tongue to a height higher than the level of the ball so that the towing vehicle may be backed up until the ball is near alignment below the socket of the trailer portion of the hitch. Since the driver of the vehicle is unable to see either the trailer tongue or the hitch ball when backing toward the trailer, it is nearly impossible to align the trailer tongue above the hitch ball during backing of the vehicle. Furthermore, a substantial danger exists that the vehicle will be backed too far, resulting in damage to the rear of the body of the towing vehicle.
This problem is conventionally solved by utilizing a second person to signal to the driver. Without the second person, however, it is necessary for the driver to back up a small distance, get out of the vehicle and inspect the relative positions of the ball and the socket, and return to the vehicle and back up further, often repeating this sequence several times. The trailer is then manually rolled or pivoted to obtain correct alignment and then the caster wheel is raised to cause a lowering of the tongue socket onto the ball.
A desirable solution to this problem is to provide a V-shaped guide about and slightly above the ball and mounted to the vehicle. Such guides are shown in U.S. Pat. Nos. 3,420,549; 3,765,703; 3,773,356; and 4,226,438.
These prior art guides, however, suffer from a variety of disadvantages which cause corresponding problems.
For example, in order for the guide to be effective, the extending arms which guide the ball socket into the central position above the ball must extend sufficiently aft of the vehicle that they intercept a misaligned tongue and guide it laterally to the center of the vehicle where the ball is located as the vehicle moves rearwardly. However, when the arms extend sufficiently far to be effective as a guide, they interfere with the articulation between the vehicle and the tongue by striking the tongue when the vehicle makes a sharp turn to the left or the right or when backing. This can cause severe damage to the guide, the hitch, the trailer, or the towing vehicle.
U.S. Pat. No. 3,420,549 attempts to solve this problem by providing pivotable arms. However, these arms require manual manipulation and fastening in their outwardly extended position and, furthermore, require a large unsightly structure on the back of the towing vehicle which is undesirable when the vehicle is being used without towing. Additionally, it requires relatively moving parts which are subject to wear, corrosion and malfunction.
U.S. Pat. Nos. 3,773,356 and 4,226,438 provide units with a fixed guide. However, such a fixed guide not only provides a permanent, unsightly attachment to the rear of a vehicle, but in addition requires a trade-off between making the arms extend sufficiently long to be effective and yet sufficiently short not to interfere with the articulation of the vehicle and the trailer.
Yet another problem arises if a driver backs the towing vehicle too rapidly against the trailer tongue. Often, if the arms of the V-shaped guide strike the trailer with excessive force, the arms or other portion of the device are bent and can no longer function properly.
Although ball-type trailer hitches all operate on the same principle, they come in a variety of dimensional variations. The draw bars as well as step bumpers, such as is common on pickup trucks, come in a variety of configurations and widths and the ball socket units come in a variety of widths and these dimensions are dependent on both ball diameter and manufacturer's specifications.
It would be desirable to have a single, universal, guide unit which is mountable to any towing vehicle having a hitch of the ball type and which can accommodate any size of ball socket. It is undesirable to require any significant modification to the towing vehicle, such as by welding additional supports onto the tow bar, in order to attach the guide unit to the towing vehicle. Such modification would cause an extensive and expensive effort to install the guide unit and results in a permanent attachment which cannot conveniently be removed, for example when selling the towing vehicle.
It is therefore an object of the present invention to provide a hitching guide which can be inexpensively mass produced as a universal structure which will fit all hitching bars and can be adjusted to properly position a ball socket directly above a ball so that they will engage when the caster wheel is raised to lower the tongue of the trailer.
Another object of the present invention is to provide a guide which can be attached to any hitching bar of any width without the necessity of additional bolts or welding to the vehicle and which can be easily removed as simply as removing the ball. After the ball is removed, the draw bar or an equivalent step bumper can be used as a hitch of the type using a vertical pin instead of a ball. Thereafter, the guide embodying the present invention is simply remounted.
Another object and feature of the present invention is to provide a hitching guide which will have arms which extend sufficiently far to be fully effective and yet which can be very easily removed with a minimum of manipulation after a trailer is connected to the hitch ball or when no trailer is being towed.
Another object and feature is to provide a hitching guide which is resilient to prevent deformation from an excessively hard collision with a trailer tongue and yet is sufficiently rigid and simple in design to be practical and feasible.